java - 为什么Java不能正确计算逻辑右移？

Question

我刚刚了解了逻辑右移。为什么我的java计算不正确？ 示例:

public class Operators {

    public static void main(String[] args) {
        byte z = -16;
        System.out.println((z >>> 2));
    }    
}

为什么Java输出:1073741820

-16 = 1111 0000
-16 >>> 2 = 0011 1100 = 60

感谢您的帮助:)

Answer 1

无符号右移运算符>>>不使用符号位来填充尾随位置。它始终用 0 填充尾随位置。

public class Main {
    public static void main(String[] args) {
        String s = "00000000000000000000000000000000";
        byte z = -16;
        System.out.println("z in decimal: " + z + ",              binary: " + s.substring(Integer.toBinaryString(z).length())
                + Integer.toBinaryString(z));
        System.out.println("z >>> 1 in decimal: " + (z >>> 1) + ", binary: "
                + s.substring(Integer.toBinaryString(z >>> 1).length()) + Integer.toBinaryString(z >>> 1));
        System.out.println("z >>> 2 in decimal: " + (z >>> 2) + ", binary: "
                + s.substring(Integer.toBinaryString(z >>> 2).length()) + Integer.toBinaryString(z >>> 2));
    }
}

输出:

z in decimal: -16,              binary: 11111111111111111111111111110000
z >>> 1 in decimal: 2147483640, binary: 01111111111111111111111111111000
z >>> 2 in decimal: 1073741820, binary: 00111111111111111111111111111100